<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title></title>
    <script src="https://cdn.bootcss.com/xlsx/0.12.13/xlsx.full.min.js" type="text/javascript" charset="utf-8"></script>
    <!--<script src="js/xlsx.full.min.js" type="text/javascript" charset="utf-8"></script>-->
    <!--原文https://www.jianshu.com/p/74d405940305-->
</head>
<body>
    <div style="width: 1100px;margin: 0 auto;">
        <div style="color: #333;line-height: 32px;">请在最新主流浏览器上使用！请确保json数据完整且格式正确！</div>
    	<button onclick="downloadExl()">导出</button>
		<textarea id="demo" rows="36" style="width: 100%;margin-top: 20px;"></textarea>
	    <!--以下a标签不需要内容-->
	    <a href="" download="这里是下载的文件名.xlsx" id="hf"></a>
    </div>
    <script>
        var tmpDown; //导出的二进制对象
        function downloadExl(type) {
        	var json = JSON.parse(document.getElementById("demo").value);
            var tmpdata = json[0];
            json.unshift({});
            var keyMap = []; //获取keys
            //keyMap =Object.keys(json[0]);
            for (var k in tmpdata) {
                keyMap.push(k);
                json[0][k] = k;
            }
          	var tmpdata = [];//用来保存转换好的json 
            json.map((v, i) => keyMap.map((k, j) => Object.assign({}, {
                v: v[k],
                position: (j > 25 ? getCharCol(j) : String.fromCharCode(65 + j)) + (i + 1)
            }))).reduce((prev, next) => prev.concat(next)).forEach((v, i) => tmpdata[v.position] = {
                v: v.v
            });
            var outputPos = Object.keys(tmpdata); //设置区域,比如表格从A1到D10
            var tmpWB = {
                SheetNames: ['mySheet'], //保存的表标题
                Sheets: {
                    'mySheet': Object.assign({},
                        tmpdata, //内容
                        {
                            '!ref': outputPos[0] + ':' + outputPos[outputPos.length - 1] //设置填充区域
                        })
                }
            };
            tmpDown = new Blob([s2ab(XLSX.write(tmpWB, 
                {bookType: (type == undefined ? 'xlsx':type),bookSST: false, type: 'binary'}//这里的数据是用来定义导出的格式类型
                ))], {
                type: ""
            }); //创建二进制对象写入转换好的字节流
            var href = URL.createObjectURL(tmpDown); //创建对象超链接
            document.getElementById("hf").href = href; //绑定a标签
            document.getElementById("hf").click(); //模拟点击实现下载
            setTimeout(function() { //延时释放
                URL.revokeObjectURL(tmpDown); //用URL.revokeObjectURL()来释放这个object URL
            }, 100);
        }

        function s2ab(s) { //字符串转字符流
            var buf = new ArrayBuffer(s.length);
            var view = new Uint8Array(buf);
            for (var i = 0; i != s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
            return buf;
        }
         // 将指定的自然数转换为26进制表示。映射关系：[0-25] -> [A-Z]。
        function getCharCol(n) {
            let temCol = '',
            s = '',
            m = 0
            while (n > 0) {
                m = n % 26 + 1
                s = String.fromCharCode(m + 64) + s
                n = (n - m) / 26
            }
            return s
        }
    </script>
</body>
</html>
